Cellular and Molecular Mechanisms of Learning in the Zebrafish

描述(申请人提供)：了解学习和记忆的神经生物学基础是现代神经科学中最重要的问题之一。目前有几种模式生物被用来研究学习和记忆。然而，目前还没有一种生物将快速的胚胎发育、适合正向和反向遗传操作、电生理易驯化以及脊椎动物基因组和神经系统结合在一起。这项提议的目的是将斑马鱼发展成为一种有用的模式生物，用于学习和记忆的细胞生物学分析。斑马鱼作为学习和记忆研究的模式生物有几个优点。它既适用于正向遗传，也适用于反向遗传。此外，斑马鱼有一种简单的反射性逃避反应，即C-Start，这种反应是由斑马鱼后脑和脊髓中相对简单的神经回路介导的。这个回路中的许多神经元已经被识别出来，并从电生理角度进行了记录。C-Start反射将用于研究简单形式的非联想记忆和联想记忆的遗传基础，包括习惯化、去习惯化、敏感化和经典条件反射。将制定短期和长期学习协议。另一个主要目标将是开发反向遗传工具，以识别斑马鱼中对学习和记忆重要的基因。为此，将开发一种使用RNA干扰(RNAi)来干扰特定基因(基因敲除)表达的方法。此外，还将开发一种计算机屏幕来识别斑马鱼中与学习相关的基因。然后，这些基因将成为学习和记忆研究中基因敲除的目标。预计这项研究的发现将加快斑马鱼发展成为记忆研究的模式生物。此外，拟议中的实验结果将有助于从根本上理解学习和记忆的基础过程。这样的理解将有助于开发治疗阿尔茨海默病和其他记忆障碍的方法。

DESCRIPTION (provided by applicant): An understanding of the neurobiological basis of learning and memory is one of the most important problems in modern neuroscience. At present there are several model organisms that are used to study learning and memory. No one organism, however, currently combines rapid embryological development, suitability for forwards and reverse genetic manipulation, electrophysiological tractability and a vertebrate genome and nervous system. The purpose of this proposal is to develop the zebrafish into a useful model organism for a cell biological analysis of learning and memory. The zebrafish has several advantages as a model organism for the study of learning and memory. It is suitable for both forwards and reverse genetics. In addition, the zebrafish possesses a simple reflexive escape response, the C-start, which is mediated by a relatively simple neural circuit in the fish's hindbrain and spinal cord. Many neurons within this circuit have already been identified and electrophysiologically recorded from. The C-start reflex will be used to investigate the genetic basis of simple forms of nonassociative and associative memory, including habituation, dishabituation, sensitization and classical conditioning. Both short-term and long-term learning protocols will be developed. Another major goal will be to develop reverse genetic tools for identifying genes that are important for learning and memory in the zebrafish. Toward this end a methodology for disrupting the expression of specific genes (gene knockdown) using RNA interference (RNAi) will be developed. In addition, a computational screen will be developed to identify learning-associated genes in the zebrafish. Such genes will then become targets for gene knockdown in studies of learning and memory. It is expected that the findings from this study will speed the development of the zebrafish into a model organism for memory studies. In addition, the results from the proposed experiments will contribute to a fundamental understanding of the processes that underlie learning and memory. Such an understanding will facilitate the development of treatments for Alzheimer's disease and other disorders of memory.